cardiac sarcoidosis

Cardiac involvement of sarcoidosis is a manifestation of sarcoidosis which is often asymptomatic, although can be associated with high mortality . Autopsy studies show prevalence of ~25% cardiac involvement, yet only 5-10% are found symptomatic .

Sarcoidosis is a multisystem disorder characterized by the presence of non-caseating granulomas. For a general discussion on the disease, please refer to the main sarcoidosis article.

Epidemiology

Up to 33% of sarcoidosis may manifest as isolated cardiac involvement .

Clinical presentation

Most cases of autopsy-proven cardiac sarcoidosis are not clinically symptomatic . Additionally, ~25% (range 13-39%)  with imaging findings suggestive of cardiac involvement are thought to be asymptomatic.

Nonetheless, symptomatic cardiac sarcoidosis often presents with severe cardiac derangement and is the primary manifestation of sarcoidosis in these patients.

Symptomatic cardiac sarcoidosis has a nonspecific presentation :

• arrhythmias - e.g. sudden death (most common), heart block, syncope
• congestive cardiac failure
• angina pectoris (i.e. chest pain)
• ventricular aneurysm formation

Although the involvement of the pericardium is rare, constrictive pericarditis has been described .

Pathology

Cardiac sarcoidosis is an inflammatory process that results in scarring, most commonly of the interventricular septum, posterior left ventricle, right ventricle, and anterior left ventricle . Cardiomegaly is often frequently present .

Definitive diagnosis requires pathology confirmation of noncaseating granuloma by endomyocardial biopsy, although sensitivity is poor .

Radiographic features

Although the disease may involve either the left or the right ventricle, the left ventricle is involved most commonly.

CT

• rarely seen on CT; myocardial thinning may be the only sign  although extra-cardiac thoracic manifestations may be present (i.e. pulmonary changes, lymphadenopathy)
• cardiomegaly, pericardial effusions and ventricular aneurysms may also be present

MRI

MRI is the modality of choice, although MR findings of cardiac sarcoidosis are non-specific:

• a variable pattern of late gadolinium enhancement
  • typically mid-wall and/or epicardial, sparing subendocardium
  • basal heart, particularly septum and lateral wall
• nodular mid-wall hyperintense foci on black blood T2-weighted imaging
• areas of focal myocardial thickening

Positive findings without clinical correlate are thought to potentially represent subclinical disease .

F FDG-PET

• PET may be useful for disease detection and treatment response
• active disease manifests as heterogenously increased myocardial uptake

Echocardiography

Transthoracic echocardiography demonstrates a spectrum of changes, often subtle as left ventricular systolic function is preserved during the early stages of the disease, including :

• diastolic dysfunction
  • occurs early in the course of the disease
  • preserved left ventricular ejection fraction
• decreased left ventricular wall thickness
  • antecedent focal thickening is thought to be due to granuloma formation, followed by fibrosis and contractile dysfunction
  • associated with dyskinetic wall motion affecting the basal inferolateral (posterior) and basal septal walls
  • basal inferolateral/septal walls are easily visualized from the parasternal long axis and apical 4 chamber views

Treatment and prognosis

Cardiac sarcoidosis may account for around 13-25% of deaths from sarcoidosis. Early treatment options include corticosteroids or other immunosuppressive agents. Other treatments would include placement of a pacemaker or implantable defibrillator to prevent sudden death. In refractory cases, cardiac transplantation may be an option.

Siehe auch:

• Sarkoidose
• Neurosarkoidose
• pulmonale und mediastinale Sarcoidose
• Pericarditis constrictiva
• abdominelle Manifestationen der Sarkoidose
• sarcoidosis (general article)

und weiter:

• Sarkoidose der Leber
• kardiale Amyloidose
• differential diagnosis of delayed myocardial enhancement on MRI